Because the R/C mobiles crane only lasts for 5 1/2 hours before needing a recharge, I thought it needed supplimenting with a second to keep exhibition interest.
Instead of building a duplicate, I've made a 'steam' rail crane, narrow gauge, on 14mm track which I've just got working.
It has all the functions - slew, derrick, hoist and travel, and with a 1000mAh lipo, it should last a full day.
There are still a couple of details to add to finish it off.
Hiding underneath all that junk is a slip-ring, which allows 360 degree plus rotation of the crane on the frames.
The only power conducted through is two ways for the traction motor,
which is yet another 6v gearmotor, second axle driven by the first via a gear-train of laser-cut gears.
